Steam iron

ABSTRACT

The invention is directed to a balanced pressure steam iron having a closed water tank and steam generating soleplate with control means to start and stop a metered flow of water. It has pressure balancing means connecting the steam generating soleplate and tank and a power spray means connected to the tank. In this conventional iron the invention provides an improvement in means to control pressure in the tank by supplying a coverplate overlying the soleplate to define steam passages therebetween and pressure ocntrol is provided by a continuously open pressure controlling conduit through the coverplate, the conduit containing an orifice and being formed to repel foreign particles whereby the single continuously open conduit controls both pressure within the iron and vents the iron for filling or emptying when upended.

[1 3,780,457 Dec. 25, 1973 United States Patent [17 1 Gowdy et al.

Primary Examiner-Patrick D. Lawson Att0rney-George R. Powers et al.

STEAM IRON Inventors: Harold W. Gowdy; William E.

Davidson, both of Ontario, Canada [57] ABSTRACT The invention is directed to a balanced pressure steam Assignee: General Electric Company,

Bridgeport, Conn.

Feb. 5, 1973 Appl. No.: 329,365

iron having a closed water tank and steam generating soleplate with control means to start and stop a me- [22] Filed:

tered flow of water. It has pressure balancing means connecting the steam generating soleplate and tank and a power spray means connected to the tank. In this conventional iron the invention provides an improvement in means to control pressure in the tank by supplying a coverplate overlying the soleplate to de- 16 v 80% 7 5 w? 36th 8 7 7 1 C &t n U1 1]] 2 00 555 38/77'8 fine steam passages therebetween and pressure ocntrol is provided by a continuously open pressure control- Field of seaPZi'IIIIII....fIfffffffIfII ling conduit through the coverplate, the conduit containing an orifice and being formed to repel foreign 7-8l particles whereby the single continuously open conduit controls both pressure within the iron and vents /7 81 the iron for filling or emptying when upended.

38/77.8l Young et al.

References Cited UNITED STATES PATENTS 3,045,370 7/1962 Foster................................ 3.103.079 9/1963 Bricker et al..... 3,156,054 ll/l964 Davidson 3,337,975 8/1967 7 Claims, 3 Drawing Figures 1 STEAM IRON BACKGROUND OF THE INVENTION 1. Field of the Invention:

The invention is directed to a steam iron and, more particularly, to a balanced pressure steam iron preferably but not limited to a power spray of the general types shown in U.S. Pat. No. 3,045,370 of common assignment where an internal pressure of several pounds is created and used to operate a power spray. This is generally known as a balanced pressure steam iron. The present invention improves on such iron by eliminating the usual pressure control valve within the iron and also eliminates the usual ball check vent valve that is upended for so the ironmay be filled or emptied when upended. The invention combines these two functions in one simplified continuously open conduit that contains a pressure control orifice to achieve the same functions with fewer parts.

2. Description of the Prior Art:

With the advent of irons using water for either steam or spray purposes or both, it is customary to provide a water tank above the soleplate and use a water valve to provide controlled and metered water drippage into'a steam geherating cavity where it flashes to steam and is directed out ports in thesoleplate to steam the article. This is a flash boiler steam iron and is typical of most stesm irons today. Additionally, spray attachments, either powered by steam or manual, have been added to such irons to supply a fine spray from the water tank to spray onto the garment. In order to use the pressure created, to operate the spray, it is possible to pressurize the iron or retain the generated steam within the iron until sufficient pressure has been built up to power the spray if present, and then release the steam to the sole-plate by means of a pressure control valve. This is known as a balanced pressure steam iron since the pressure generated must be communicated to the upper portion of the water tank in order to balance the pressure so that the metered water can flow into the generator. Sufficient pressure may be generated to operate a power spray. Additionally, when the iron is upnded for filling or emptying, it is customary to provide a valve, such as a ball check valve, that vents the tank usually through the soleplate so that water may be poured into or out of the iron. Generally, these two control valves pressure control and vent have comprised two separate valves operating independently of one another and requiring separate parts. Prior art constructions have not provided a simplified version wherein a simple continuously open conduit replaces the normalpressure control valve and the vent valve. Copending application Ser. No. 305,574 filed Nov. 10, 1972 and of common assignment discloses a form of the present invention as applied to a combination in a Y self-cleaning steam iron whereas the basic construction of the instant application is generally applicable to any balanced pressure iron and is generic to the selfcleaning application.

SUMMARY OF THE INVENTION Briefly described, the present invention is directed to an improved steam iron of the balanced pressure type which has a closed water tank and steam generating soleplate with ports andpcontains steam control means that includes a valve to start and stop a metered flow of water from the tank to a soleplate steam generating cavity. A pressure balancing means connects the steam generating cavity and tank and, in the illustrated model, a power spray means is connected to the tank so that the spray may be powered by steam pressure. In this known combination the invention provides an improvement in the means to control steam pressure and thus pressure in the tank to operate the spray and also to" vent the tank which comprises a coverplate that overlies the soleplate to define steam passages between the two. A means is provided connecting the cavity and passages to admit steam tp the passages fromthe cavity. This connecting means comprises a continuously open pressure controlling conduit through the coverplate, the conduit including a separate pressure control orifice which may include means to screen out foreign particles and, in the event some particles penetrate the screen, the orifice is formed as a cone to inherently BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevational view, partially in section and broken away, showing general parts of a steam iron with the invention;

FIG. 2 is a partial exploded perspective of the upper portion of the coverplate showing the invention as applied to the flash boiler type iron; and

FIG. 3 is a partial enlarged split view of the pressure control and vent conduit showing two modifications.

DESCRIPTION OF THE PREFERRED EMBODIMENT The invention is described in connection with a steam iron of the balanced pressure type although it is equally applicable to manual spray steam irons and may be applied to steam irons of the flooded boilertype as generally shown in U.S. Pat. No."3,l56,054, non-flash boilertype shown in U.S. Pat. No. 2,810,218 both of common assignment, or the common flash or flooded boiler-type described herein with or without a spray attachment. For convenience, the invention is described in connection with a power spray balanced pressure stesm iron. Referring first to FIG. 1, there is shown a steam iron that includes soleplate 10 having plural steam ports 12 and outer shell 14 connected in any suitable manner to handle 16 all in known fashion. Soleplate 10 may be cast aluminum with an electrical heating element 18 cast in position. The heating element is generally of the sheath type and extends in a loop beginning at the rear of the iron along one side to the forward end and then rearwardly along the other side. Thus, substantially uniform heat distribution is provided to the soleplate.

The iron includes means for generating steam by providing interior closed water tank 20 which may have a vertical outer suitably-shaped riser tube means 22 in the forward portion for housing various operating mechanisms or this may be omitted. For steam, soleplate 10 has a steam generating cavity 24 to receive metered water. Steam control means is provided and includes well-known water valve structure, generally indicated at 26, to start and stop a metered flow of water from the tank to steam generating cavity 24 and activated by meanslsuch as button 28 through connected spring-biased vertical stem 30 and water is thus metered through an orifice 32 from the water tank to the generator as indicated in the referenced patents and said copending application and well-known in the art. A conventional known fill valve structure 34 is part of water valve 26 and serves to close the tank when steam button 28 is in the up position shown permitting water to be metered through orifice 32 to be flashed into steam. The resulting steam is distrubuted and directed through steam passages 36 formed with overlying coverplate 38 and lying between the coverplate and soleplate as seen in FIG. 1. The steam then passes out ports 12 onto the fabric in a well-known manner. A power spray attachment 40, energized by steam pressure in the general manner disclosed in U.S. Pat. No. 3,041,757 of common assignment, may be provided and operated by control button 42 to provide a continuous spray on one depression of button 42. A conventional temperature control, not shown, operates to thermostatically control the heat generated in the soleplate. To assure a continuous flow into cavity 24, the steam pressure generated is communicated to the upper surface of the water in tank by means of balance tube 44 to provide the balanced pressure system and enable water to flow. It has been customary to provide a pressure control valve and a separate vent means, as generally disclosed in said 3,045,370 U.S. Pat., in order to provide a controlled pressure build-up and a valve to vent the iron so that it may be refilled when fill valve 34 is unseated as steam button 28 is depressed to stop water flow. The structure thus far described is well-known and generally shown in the issued patents referenced.

In accordance with the invention, the usual pressure control valve and separate venting valve are omitted and replaced by a single continuously open pressure controlling conduit connecting the steam generating cavity 24 and the steam distributing passages 36. There is nothing to seat and therefore no moving parts and the single conduit replaces the two previous valves while performing the functions of both. As applied to the flash boiler steam iron as shown in FIG. 1 and the left side of FIG. 3, the conduit may be any suitable through conduit 46 that is conveniently formed directly in the coverplate as shown. In order to control the pressure through the conduit, it is provided with a pressure control orifice plate 48 having an orifice 50 formed directly therein as shown in FIG. 3. The selected size of orifice 50 will obviously control the pressure by controlling the rate of flow into passages 36. In a typical power spray application it is selected so that the iron operates under about 3 pounds pressure. The orifice plate 48 may be easily inserted into a stepped portion in conduit 46, as shown, and retained therein by snapping a screening means 52 over the orifice to protect it from foreign particles. Typically, the openings in screen 52 will be smaller than orifice 50 so that any particles passing through the screen would tend to pass through the orifice and not clog it. In order to further protect the orifice against any foreign particles that do get past the screen or are formed below it, the orifice is formed with sloping sides 54 that inherently repel and tend to direct any foreign particles away from the orifice. Conveniently, the sides are formed as an upward cone on the outer surface as shown in FIG. 3. This sloping side feature is cumulative to the screening in repelling or shedding foreign particles.

While any suitable continuously open pressure controlling conduit is satisfactory, in order to prevent the carry-over of condensation on initial steam flow when the iron is first activated, the conduit is formed with a high entrance in the steam generating cavity. In other words, the entrance to the conduit is disposed above the low point of the coverplate so that any condensation trapped must evaporate before it can enter the passages 36 as steam. With this arrangement, it can be seen on the left side of FIG. 3, that the orifice is then below the top of the conduit to provide the sloping sides and screening and achieve these desirable objects in a low overall height with very few and simple parts.

The iron described operates under pressure for the purpose of powering the spray, but also even without the spray it is necessary to maintain a suitable minimum pressure in order to steam satisfactorily through the ports in the soleplate. When the iron is upended on its heel to terminate the ironing or when it is desired to refill or empty the iron, it is necessary to vent the tank in order to obtain flow. As described, the open conduit with its pressure control orifice 50, acts also in a dual fashion as a venting means since the air in the water tank simply flows through the balance tube, through the conduit, and through the soleplate thus offering no restriction to refilling or emptying of the iron and venting the tank. The invention has thus far been described as applied to a balanced pressure steam iron of the flash boiler type shown on the left of FIG. 3 as it may be used with or without a power spray.

The invention is equally applicable to the flooded boiler concept with slight structural modifications. In this concept, as generally described in said 3,156,054 U.S. Pat., orifice 32 permits water flow into generating cavity 24 at a rate greater than the rate at which steam is formed in the cavity so the cavity remains flooded up into the balance tube 44 while heat transfer to the water tank is minimized. As seen on the right side of FIG. 3, steam formed is separated from the remaining water in the cavity and bubbles up through the water and balance tube into the water tank for balanced pressure. The steam is then directed by an extension 47 of conduit 46 which extends above the water in the tank. Conveniently, the conduit and extension may be disposed in balance tube 44 as shown at the right in FIG. 3. The steam passes down conduit 47/46 into steam passages 36 and thence to the fabric being ironed to provide a supply of wet steam. The screen 52 may be supplied as before'or omitted as desired. Also the orifice 50 may be separate in the conduit as shown, or to simplify sealing problems, may be alternatively located at 51 above the water level. Again the continuously open pressure control and vent orifice 50/51 provides the same functions in the same manner as previously described.

It will be seen that the substitution of the continuously open pressure control orifice in the balanced pressure or closed water tank iron described, enables the omission of the usual pressure control valve as well as the vent valve. It lowers the overall height of the parts normally present in the flash boiler and greatly simplifies the flooded boiler, and it serves the function of both pressure control and venting to simplify and reduce the cost of the iron.

While there have been shown preferred forms of the invention, obvious equivalent variations are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practised otherwise than as specifically described, and the claims are intended to cover such equivalent variations.

1 claim:

1. In a steam iron having a closed water tank and steam generating soleplate with ports, steam control means including a valve to start and stop a metered flow of water from the tank to a soleplate steam generating cavity, pressure balancing means connecting the cavity and tank, the improvement in means to control pressure in the tank comprising,

a coverplate overlying the soleplate to form steam passages therebetween,

means connecting the cavity and passages to admit steam thereto, said means comprising a continuously open pressure controlling conduit through said coverplate,

whereby the ssme conduit both controls pressure and vents the iron.

2. Apparatus as described in claim 1 wherein said conduit includes a separate pressure control orifice and is spaced from said steam control means.

. 3. Apparatus as described in claim 2 wherein said orifree is formed with sloping sides to repel foreign particles.

4. Apparatus as described in claim 3 wherein said ori free is formed as an upward cone on its outer surface to repel the foreign particles.

5. Apparatus as described in claim 4 having means over the orifice to screen out foreign particles,

said means having openings smaller than the orifice.

6. Apparatus as described in claim 5 wherein the entrance to said conduit is disposed above the low point of the coverplate and the orifice is below the top of the conduit.

7. Apparatus as described in claim 5 wherein the entrance to said conduit is disposed above the water level in said water tank. 

1. In a steam iron having a closed water tank and steam generating soleplate with ports, steam control means including a valve to start and stop a metered flow of water from the tank to a soleplate steam generating cavity, pressure balancing means connecting the cavity and tank, the improvement in means to control preSsure in the tank comprising, a coverplate overlying the soleplate to form steam passages therebetween, means connecting the cavity and passages to admit steam thereto, said means comprising a continuously open pressure controlling conduit through said coverplate, whereby the ssme conduit both controls pressure and vents the iron.
 2. Apparatus as described in claim 1 wherein said conduit includes a separate pressure control orifice and is spaced from said steam control means.
 3. Apparatus as described in claim 2 wherein said orifice is formed with sloping sides to repel foreign particles.
 4. Apparatus as described in claim 3 wherein said orifice is formed as an upward cone on its outer surface to repel the foreign particles.
 5. Apparatus as described in claim 4 having means over the orifice to screen out foreign particles, said means having openings smaller than the orifice.
 6. Apparatus as described in claim 5 wherein the entrance to said conduit is disposed above the low point of the coverplate and the orifice is below the top of the conduit.
 7. Apparatus as described in claim 5 wherein the entrance to said conduit is disposed above the water level in said water tank. 